The present invention relates to a method and apparatus of displaying bit stream data, a method and apparatus for generating bit stream data, and a storage medium.
In an apparatus which displays bit stream data (e.g., a moving-picture bit stream or audio bit stream; the moving-picture bit stream may be accompanied with speeches), it is required to execute a related program in synchronism with the display operation.
In a case of dealing with multimedia data which consists of a mixture of a moving-picture bit stream and a program, for example, displaying moving pictures may be synchronized with execution of a program in the following manner.
(a) A moving-picture bit stream is adequately read out and displayed on the display screen accompanied with execution of a program.
(b) The program detects the end of image display and starts the next operation.
The following problems however arise when multimedia data consisting of a mixture of a moving picture bit stream and a program is broadcast and reproduced in real time, or when multimedia data consisting of a mixture of a moving-picture bit stream and a program is read out from a storage medium like DVD and reproduced in a time sequential order.
(a) At the time of reproducing moving pictures accompanied with the program execution, reception or reading of moving-picture bit stream data has not been completed yet.
(b) When image display is finished, reception or reading of a program to be executed has not been completed yet.
Further, since it is not known when a program code will be invoked, every program code must always stand by for execution. This leads to such a disadvantage that a reception terminal requires a vast amount of resources.
Accordingly, it is an object of the present invention to provide a method and apparatus of displaying bit stream data, a method and apparatus for generating bit stream data, and a storage medium, all of which ensure smooth synchronization of reproduction of a bit stream with execution of an associated program and efficient use of resources.
According to one aspect of the present invention, there is provided a data display method comprising the steps of: receiving data having a program unit and instruction data for the program unit multiplexed on bit stream data; extracting the program unit from the received data and storing the extracted program unit in a memory; extracting the instruction data from the received data, reading the program unit or part thereof specified by the extracted instruction data from the memory, and executing the read program unit or the part thereof; and displaying the bit stream data and the execution result.
According to another aspect of the present invention, there is provided a data generating method comprising the steps of: determining a program unit to be used in association with bit stream data; determining instruction data for the program unit, which is to be embedded in the bit stream data in accordance with a timing for executing the program unit; and arranging the program unit and the instruction data in the bit stream data.
According to another aspect of the present invention, there is provided a storage medium storing computer-executable program code comprising: means for causing a computer to receive data having a program unit and instruction data for the program unit multiplexed on bit stream data; means for causing a computer to extract the program unit from the received data and store the extracted program unit in a memory; means for causing a computer to extract the instruction data from the received data, read the program unit or part thereof specified by the extracted instruction data from the memory, and execute the read program unit or the part thereof; and means for causing a computer to display the bit stream data and the execution result.
According to another aspect of the present invention, there is provided a storage medium storing computer-executable program code comprising: means for causing a computer to determine a program unit to be used in association with bit stream data; means for causing a computer to determine instruction data for the program unit, which is to be embedded in the bit stream data in accordance with a timing for executing the program unit; and means for causing a computer to arrange the program unit and the instruction data in the bit stream data.
According to another aspect of the present invention, there is provided a storage medium storing computer-readable data comprising: bit stream data; a program unit multiplexed on the bit stream data; and instruction data for the program unit, which is multiplexed at a position which comes later than a position of the program unit in the bit stream data.
According to another aspect of the present invention, there is provided a data display apparatus comprising: means for receiving data having a program unit and instruction data for the program unit multiplexed on bit stream data; means for extracting the program unit from the received data and storing the extracted program unit in a memory; means for extracting the instruction data from the received data, reading the program unit or part thereof specified by the extracted instruction data from the memory, and executing the read program unit or the part thereof; and means for displaying the bit stream data and the execution result.
According to another aspect of the present invention, there is provided a data display apparatus comprising: means for determining a program unit to be used in association with bit stream data; means for determining instruction data for the program unit, which is to be embedded in the bit stream data in accordance with a timing for executing the program unit; and means for arranging the program unit and the instruction data in the bit stream data.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinbefore.